[Standards, options and recommendations (SOR) for clinical care of malignant thymoma. Groupe de Travail SOR].

Context: The "Standards, Options and Recommendations" (SOR) project, started in 1993, is a collaboration between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcome for cancer patients. The methodology is based on literature review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery.

Objectives: To develop clinical practice guidelines according to the definitions of Standards, Options and Recommendations for the clinical care of malignant thymoma in adult.

Methods: Data have been identified by literature search using Medline (december 1998) and the expert groups personal reference lists. Once the guidelines were defined, the document was submitted for review to national and international independent reviewers, and to the medical committees of the 20 French Cancer Centres.

Results: The main recommendations for malignant thymoma management are that: 1) the clinical diagnosis is based on appropriate clinical and radiological findings; 2) the final diagnosis is pathological and made from a biopsy, except in cases of well-encapsulated tumors which are completely resected. The biopsy, via anterior mediastinostomy, should be performed by the surgeon who will subsequently perform the definitive surgery; 3) surgical resection must be complete including thymus and perithymic fat and performed by an experienced surgeon; 4) the therapeutic strategy for malignant thymoma is based on the three current staging systems and involves surgery with radiotherapy given if the capsule is invaded or penetrated. Radiotherapy should be given in experienced centres. Inclusion of patients in prospective clinical trials is recommended in order to determine the usefulness of neoadjuvant chemotherapy and multimodality approaches; 5) treatment of metastatic malignant thymoma is based on chemotherapy. Secondary surgery may be performed with the aim of achieving complete resection. Inclusion in clinical trials is recommended; 6) at the present time, there are no clear data on which to base guidelines for timing and duration of follow-up studies in this condition. Because of late recurrence, follow-up should be long.